Neutral Endopeptidase Activity is Increased in the Skin of Subjects with Diabetic Ulcers  Marcos A. Antezana, Stephen R. Sullivan, Marcia L. Usui, John E. Olerud, MD.  Journal of Investigative Dermatology  Volume 119, Issue 6, Pages 1400-1404 (December 2002) DOI: 10.1046/j.1523-1747.2002.19618.x Copyright © 2002 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 1 NEP immunohistochemistry of normal and diabetic skin. (A) Normal, unwounded skin with large arrow indicating NEP staining of basal keratinocytes and small arrows showing NEP staining of blood vessels. (B) Ulcer margin from a patient with diabetes with asterisk (*) indicating ulcer bed. Note strong NEP staining throughout the epidermis and strong dermal matrix staining. (C) Unwounded skin adjacent to the ulcer from a subject with diabetes showing strong NEP staining throughout the epidermis. (D,E) Unwounded skin from the proximal regions from two different patients with diabetes showing variability of NEP epidermal staining where D shows strong epidermal staining and E shows a staining pattern approaching that of normal skin. Scale bar=50 μm Journal of Investigative Dermatology 2002 119, 1400-1404DOI: (10.1046/j.1523-1747.2002.19618.x) Copyright © 2002 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 2 Cutaneous NEP activity (pmol MNA per h per μg) of skin homogenates determined with fluorimetric assay. For each skin sample, three fluorimetric readings were averaged and compared with a standard curve to determine NEP activity. Results are mean±SD. Journal of Investigative Dermatology 2002 119, 1400-1404DOI: (10.1046/j.1523-1747.2002.19618.x) Copyright © 2002 The Society for Investigative Dermatology, Inc Terms and Conditions